BUG #2118: could not connect to server

The following bug has been logged online:

Bug reference: 2118
Logged by: zhuge xiao
Email address: zhuge(at)Rinaix(dot)cn
PostgreSQL version: 8.0.3
Operating system: Linux ( FC4 )
Description: could not connect to server
Details:

Help me!

I have edited the program testlibpq.c which is copied from the PostgreSQL
document to make it become a CGI program. And I have succeeded to compile
the programme, testlibpq.c from the command line:
[zhuge(at)xiao2 src]$ cc -o testlibpq testlibpq.c -lpq

And it can run from the command line:
[zhuge(at)xiao2 src]$ ./testlibpq

Then, I copied the excuteable program to the CGI directory,
/var/www/cgi-bin. And let it run from the Mozilla Firefox browser whose URL
was http://localhost/cgi-bin/testlibpq. But I failed. The result was that
the below message was displayed in the browser:
could not connect to server: Permission denied
Is the server running locally and accepting connections on Unix domain
socket "/tmp/.s.PGSQL.5432"?

The above message was produced by the below code:
if (PQstatus(conn) != CONNECTION_OK)
{
fprintf(stdout, PQerrorMessage(conn));
exit_nicely(conn);
}

How can I do? Please help me!

Thank you very much.

zhuge(at)Rinaix(dot)cn